Winter Flounder fish identification, Habitats, Fishing methods, fish characteristics
The Winter Flounder, also known as Lemon Sole is a flatfish of the family Pleuronectidae. They are native to coastal waters of the western north Atlantic coast, from southern Labrador, Canada to South Carolina and Georgia, United States. It is one of the most stationary of fishes, displaying a very limited seasonal migration. Fish stay overwinter in inshore areas. Adult species migrations consist of two phases; an autumn estuarine immigration prior to spawning, and a late spring/summer movement to either deeper, cooler portions of estuaries or to offshore areas after spawning.
The Winter Flounder, Pseudopleuronectes americanus, also known as Black Back, Lemon Sole, Blackback, Georges Bank Flounder, Sole; Flatfish, Rough Flounder, Mud Dab, Black Flounder, is a flatfish of the family Pleuronectidae. They are native to coastal waters of the western north Atlantic coast, from southern Labrador, Canada to South Carolina and Georgia, United States, it is most abundant from the gulf of St. Lawrence to the Chesapeake Bay, the most common near-shore flounder in the shallow-waters from Newfoundland down through Massachusetts Bay. It spends the summer off shore in deeper waters, and winters in shallow coastal estuaries rivers and bays.
This is a small-mouthed, right-handed species having eyes on the right side and viscera on the right. The eyes are located on its upper surface when the fish is pointing to the right. Their dorsal fin rays originates opposite the forward edge of the eye, and is of nearly equal height throughout its length. Anal fin is highest about midway, and it is preceded by a short, sharp spine. Its ventral fins are alike on the two sides of the body, and both of them are separated from the long anal fin by a considerable gap. The mouth is small, not gaping back to the eye, and the lips are thick and fleshy like those of the yellowtail. The left (under) half of each jaw is armed with one series of close-set incisor-like teeth, but the right (upper) side has only a few teeth, or it may even be toothless. The scales are rough on the eyed side, including the space between the eyes, but they are smooth to the touch on the blind (white) side.
Eyed side has variable color from tannish, reddish brown, olive green to dark slaty or black. Blind side is white, but could be yellow on lower peduncle, some species could be with dark blotches. Mouth is small, snout is short. Area between eyes is scaled. Lateral line straight over pectoral fin.
The eyes are on the right side
The lateral line is straight
Color is the darkest of all the flatfish
60 to 76 Dorsal fin rays.
45 to 58 Anal fin rays.
Max. length 64 cm
Max. weight 3.6 kg.
Coloring often varies with habitat, in accordance with the bottom on which they lie, ranging from muddy to slightly reddish brown, olive green, dark slate, to an almost black upper. May be uniformly colored, mottled, blotched, or partially white. Smaller species are paler and more marked than large species. The blind side is white, more or less translucent toward the edge, where it is often faintly tinged with bluish, and the lower side of the caudal peduncle is yellowish on some specimens, but is pure white on others. The long dorsal and anal fins are often tinged with pink, red, or yellow on the eyed side. The ventrals and pectorals of the eyed side are of the general ground tone, but their mates on the blind side are pure white. Small fish average paler and more blotched or mottled than large ones. Winter flounders usually being very dark on mud, and pale on bright sand bottoms. But field experience suggests that they have less control over shade and pattern than the
They can be differentiated from Summer Flounder because they almost always have eyes on the right side of their bodies. They also do not have teeth. Summer Flounder have their eyes on the left side of their bodies, and have teeth.
Winter flounder is easily separable from the Yellowtail Flounder, which is similarly characterized, by following: its lateral line is nearly straight (at most only slightly bowed abreast the pectoral fin), the dorsal profile of its head is less concave, its nose is blunter, its eyes are farther apart, it has fewer fin rays, and its fins are less tapering in outline. The most obvious differences between the winter flounder and the smooth flounder is that the former is rough scaled between the eyes, the latter smooth there, and that the winter flounder has the larger number of anal fin rays.
Winter Flounder is easily separable from the
Witch Flounder: it has only about 2/3rd as many dorsal rays as the witch; it lacks the mucous pits that are conspicuous on the left (lower) side of the head of the witch, and its tail is much larger proportionately than tail of the Witch Flounder (also known as Grey Sole). It is oval in outline, about 2 1/4 times as long to the base of the caudal fin as it is wide, thick-bodied, and with proportionately broader caudal peduncle and tail than any of our other small flatfishes.
They inhabit shallow enclosed bays, or harbors, where extensive flats are heated by the sun at low tide in summer but are exposed to very severe chilling in winter. The flounders tend to desert the flats for the deeper channels during the heat of summer, work back again into shoal water in autumn, desert the ice-bound flats once more in winter, and then work up again in spring. Young-of-the-year (fish born in the past year) and some one year-old fish remain in the estuaries where they were hatched throughout the year. Juveniles prefer sand or sand-silt bottoms in a wide range of salinity and temperature. Adults occupy bottom habitats in inshore bays and estuaries during the winter and deeper water in the summer. While inshore, adults prefer muddy sand, clean sand, clay, and pebbly or gravelly ground.
They are very common inshore are on muddy sand, especially where this is broken by patches of eel grass. But winter flounders are common enough there on cleaner sand, on clay, and even on pebbly and gravelly ground. And the populations on the offshore banks are on hard bottom of one type or another. When they are on soft bottom they usually lie buried, all but the eyes, working themselves down into the mud almost instantly when they settle from swimming. And flounders that live on the flats usually lie motionless over the low tide to become more active on the flood, when they scatter in search of food. They spend most of their time lying motionless, they can dash for a few yards with astonishing rapidity, to snap up any luckless shrimp, small fish or other victim that comes within reach, or to snatch a bait, as any one may see, who will take the trouble to watch them on the flats on a calm day. They are usually feed, not by rooting in the sand.
The summer temperature is low enough for their comfort close in to shore and up to a few feet of the surface all around the open coast line of the Gulf, but the winter temperatures may be too low for them, make it uncomfortable. The normal distribution of the winter flounder covers a wide range of temperature at one season or another, from a minimum close to the freezing point of salt water around Newfoundland, in Nova Scotian waters, in the Gulf of St. Lawrence, and in the shoaler parts of the Gulf of Maine in late winter, to a maximum of about 64°-66° F. in shallow water in the southwestern part of the Gulf in summer, and of perhaps about 68°-70° in the southern part of its range. Freezing temperatures (30° to 29°) drive them down into slightly warmer water.
Winter flounder are one of the most stationary of fishes, displaying a very limited seasonal migration. Fish stay overwinter in inshore areas. Adult species migrations out into deeper water in the summer and back to shoal for the winter consist of two phases; an autumn estuarine immigration prior to spawning, and a late spring/summer movement to either deeper, cooler portions of estuaries or to offshore areas after spawning. This pattern of seasonal distribution may change in the colder waters of the northern extent of the flounder’s range where it migrates to shallow water in the summer and deeper waters in the winter.
Larval and juvenile winter flounder feed on the egg, larval and adult stages of various invertebrates. Adults feed on a great variety of organisms including shrimp, clams, polychaete worms, fish fry and bits of seaweed. Winter flounder feed mainly during daylight hours and are more active during flooding or ebbing tides than during slack water periods.
Spawning occurs from January to May in cool water temperatures, 32-42°F, with peak activity during February and March. Winter flounder are named so because of their annual spawning migrations into shallow inshore water in winter and early spring. Adults tend to return to the same spawning grounds every year. Both male and female species normally reach sexual maturity at 3 years of age. Fish of both sexes as swimming in a circle, about one foot in diameter, clockwise so that the vent is outward, with the eggs from the females flowing back along the upper side of the anal fin and along the tail. After about 10 seconds of activity, they sink motionless to the bottom. Females usually produce between 500,000 to 1.5 million eggs, but up to 3.3 million have been reported. The fecundity increases with body size. Females deposit eggs on sandy bottoms and algal mats at night an average of 40 times per spawning season.
Proper temperature and salinity, dissolved oxygen, and food availability are critical to the survival of eggs during larval development. Larvae and juveniles are typically habitat saltwater coves, coastal salt ponds, and estuaries, although larvae and juveniles have also been found in open ocean areas. Unlike the floating eggs of all other local flatfish, eggs of the winter flounder clump together in masses on the bottom, they stick together in clusters. They are 0.74 to 0.85 mm. in diameter, and newly shed eggs have no oil globule, but some of them (if not all) develop one as incubation proceeds. Eggs, usually laid on clean sand, hatch 15 to 18 days at a temperature of 37° to 38°F after being released. 5 to 6 weeks after hatching, larvae settle to the bottom to begin metamorphosis. In water of about 39° the larva grows to 5 mm. in length, and the yolk is absorbed in 12 to 14 days. The vertical fin rays begin to appear in 5 to 6 weeks after hatching, at a length of about 7 mm.
A newly hatched flat fish larva has one eye in each side of its head but within months it adapts to a bottom dwelling lifestyle, by which time one eye has moved to the other side of the head. The pigment fades from the blind side; the eyed side becomes uniformly pigmented; and the little fish now lies and swims with the blind side down, after 8 weeks its metamorphosis complete when it is only 8 to 9 mm. long. Unlike most other bottom dwelling fish that rest by lying on their bellies, a flat fish rests on its side. Having both eyes on one side of its head enables the flat fish to rest on the ocean's floor while directing both eyes upward.
A 2 to 3 years old winter flounder is about 12" in length, a 9 to 10 years old fish is about 20". Female winter flounder grow faster than males and attain larger maximum sizes to about 8 pounds with a length of 25 inches and may live up to 15 years.
Anglers pursue this species in harbors, estuaries, and other sheltered situations all around the shores of the Gulf, from bridges, docks, jetties, piers, and small boats. Areas with sandy mud and patches of eelgrass providers anglers with the greatest opportunity for success.
Winter flounder provide the most enjoyable action when caught on light tackle. Most anglers use 6 to 12 foot light medium action spinning rods. Pieces of clam, large snails, pieces of seaworm, squid, shrimp, and mussels, or almost any other bait for that matter, provided the hook is small enough. Seaworms are considered the best bait for winter flounder. The key is to use very little bait; an inch of worm will work best. Winter flounder can quickly and quietly sneak in and take baits. The rod should be raised often to attract fish.